In a heavy saucepan, melt the butterStir in the flour and cook, stirring constantly, for 3 minutes.Do not brown.Whisk in the hot milk and cook, stirring, until the mixture is very thick.Season the sauce with salt to taste, hot pepper sauce and Worcestershire.Stir in the sherry and cook 2 more minutes, stirring.Add the drained oysters and artichoke hearts.Pour the mixture into a buttered 1 1/2 quart casserole.Top with lightly buttered fresh bread crumbs.Bake in a preheated 375-degree oven for 15 minutes or until bubbly and the top is golden brown.Serve with crusty French bread.Serves 8.